SCSI (Small Computer System Interface) is a standard interface for transferring data between devices on a computer bus. To attach a computer to the host bus requires a SCSI host adapter which controls the data transfer on the SCSI bus; the peripheral side must feature a SCSI controller, which is generally embedded (i.e., integral to the peripheral) in SCSI devices. SCSI is most commonly used for hard disks and tape storage devices, but also connects a wide range of other devices, including scanners, CD-ROM drives, CD writers, and DVD drives.
In the context of computer data storage, Internet SCSI (iSCSI) uses the SCSI protocol over a TCP/IP network in the context of computer data storage. It enables a machine on an IP network (initiator) to contact a remote dedicated server (target) and perform block I/O (input/output) on the server just as it would with a local hard disk. Since an iSCSI target is a SCSI device, all the commands to the target have to be SCSI commands. However, some commands (e.g., management commands) to the target may be non-SCSI commands. Thus, it would be desirable to provide a method for transmitting a non-SCSI command between a SCSI iniatior and a SCSI target.